Today, Wave Life Sciences announced that its Phase 1 trial of WVE-210201, an investigational, exon skipping therapy for boys with Duchenne muscular dystrophy (DMD) amenable to exon 51 skipping, showed positive safety and tolerability data. Based on these results, Wave announced that it will initiate a Phase 2/3 clinical trial of WVE-210201 in 2019. Wave plans to present the results of the Phase 1 trial at upcoming scientific meetings, where more details will be announced regarding the Phase 2/3 trial.

DMD is caused by a mutation in the dystrophin gene on the X chromosome that results in little or no production of dystrophin, a protein that is essential for keeping muscle cells intact. Exon skipping drugs “skip” a section of genetic code, or exon, to allow the creation of partially functional dystrophin. Sarepta Therapeutics’ Exondys 51, which targets exon 51, has already been approved by the FDA for DMD treatment. Wave’s WVE-210201 is a stereopure oligonucleotide that has been shown in preclinical studies to induce skipping of exon 51 of the dystrophin gene. Wave hopes that the stereopurity of its molecule will allow the drug to be more effective than currently available therapies because it can be given at a higher dose.

The global, placebo-controlled Phase 2/3 trial of WVE-210201 will be designed to measure efficacy, safety and dystrophin expression. Approximately 13 percent of DMD patients have a gene mutation that is amenable to therapeutic skipping of exon 51.

In the Phase 1 trial, Wave tested four different doses of WVE-210201 and after reviewing the data has selected a dose for its planned Phase 2/3 trial. Currently, WVE-210201 is also being investigated in an ongoing multi-dose, open-label extension study that is open to patients as they complete the Phase 1 trial. Results from the open-label study, including dystrophin expression from muscle biopsies, will be available in the second half of 2019.